The present invention relates to a machine for wet processing textiles and more particularly to a low-liquid jet machine for wet processing textile fabric in continuous rope form.
Jet dyeing machines have long been used in the textile industry for piece dyeing of textile fabrics in cloth rope form. In machines of this type, the cloth is laid upon itself in folds to form a plug that progresses through a dyeing chamber containing the treating liquid. The cloth is then drawn off the leading end of the plug by the force of a liquid jet acting on the rope downstream of the plug and usually assisted by a lifter reel. The jet discharges circulating treating liquid against the cloth rope and drives it to form into folds on the trailing end of the cloth rope plug. The weight of the cloth rope being added to the trailing end of the plug in combination with the weight being removed from the leading end of the plug by withdrawing of the cloth rope therefrom by the jet causes the plug to advance slowly through the treating chamber. Usually, the treating chamber contains treating liquid to a level sufficient to substantially submerge the plug, which also provides buoyancy to facilitate advance of the plug. However, it has long been sought to reduce the amount of treating liquid used in proportion to the amount of cloth being treated, i.e., the liquid to cloth ratio. A low-liquid ratio is desirable from an expense standpoint in that less treating material is necessary and less energy is necessary for heating and circulating the liquid. Of increasing importance is the advantage with low-liquid ratios of reducing the effluent that must be treated and disposed of at the end of each processing cycle.
Various attempts have been made to design jet dyeing machines that are capable of operating at low-liquid ratios with some success. For example, gas jets have been used to reduce the amount of treating liquid being circulated, which may be introduced into the circulating air to form a foam or may be atomized into the gas. Examples of such prior art are disclosed in U.S. Pat. Nos. 3,921,420; 3,949,575; 4,007,517; and 4,483,032. In all of the known prior art, however, a sufficient amount of treating liquid is required to provide at least partial submergence of the cloth rope plug for sufficient buoyancy to facilitate advance of the plug.
In all of the prior low-liquid ratio machines, there is a problem of maintaining proper circulation of the plug with minimal energy without significant reduction in capacity. A plug that is not at least partially floating in liquid will not advance as freely as a submerged plug and normally must be of smaller volume, which results in the machine having less capacity.
By the present invention, a low-liquid jet machine is provided having unique features that provide the capability of operating efficiently at high capacity with an enhanced plug formation and progression with a low-liquid ratio and with improved cloth rope circulation.